[Python-Dev] 2.5 and beyond (original) (raw)

Giovanni Bajo rasky at develer.com
Sat Jul 1 02:01:00 CEST 2006

Tim Peters <tim.peters at gmail.com> wrote:

... Incidentally, I think that lexical scoping would also deal with the problem that people often encounter in which they have to write things like "lambda x=x:" where one would think "lambda x:" would suffice. They shouldn't encounter that at all anymore. For example,

def f(x): ... return lambda: x+1 f(3)() 4 works fine in modern Pythons.

Yes but:

a = [] for i in range(10): ... a.append(lambda: i) ... print [x() for x in a] [9, 9, 9, 9, 9, 9, 9, 9, 9, 9]

This subtle semantic of lambda is quite confusing, and still forces people to use the "i=i" trick.

Giovanni Bajo

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